This paper is concerned with the finite-time synchronization problem for a class of cross-strict feedback underactuated hyperchaotic systems. Using finite-time control and backstepping control approaches, a new robust adaptive synchronization scheme is proposed to make the synchronization errors of the systems with parameter uncertainties zero in a finite time. Appropriate adaptive laws are derived to deal with the unknown parameters of the systems. The proposed method can be applied to a variety of chaotic systems which can be described by the so-called cross-strict feedback systems. Numerical simulations are given to demonstrate the efficiency of the proposed control scheme.
Adaptive Neuro-Fuzzy Inference System (ANFIS) with first order Sugeno consequent is used widely in modeling applications. Though it has the advantage of giving good modeling results in many cases, it is not capable of modeling highly non-linear systems with high accuracy. In this paper, an efficient way for using ANFIS with Sugeno second order consequents is presented. Better approximation capability of Sugeno second order consequents compared to lower order Sugeno consequents is shown. Subtractive clustering is used to determine the number and type of membership functions. A hybrid-learning algorithm that combines the gradient descent method and the least squares estimate is then used to update the parameters of the proposed Second Order Sugeno-ANFIS (SOS-ANFIS). Simulation of the proposed SOS-ANFIS for two examples shows better results than that of lower order Sugeno consequents. The proposed SOS-ANFIS shows better initial error, better convergence, quicker convergence and much better final error value.
In this paper, the problem of adaptive output feedback stabilization is investigated for a class of nonlinear systems with sensor uncertainty in measured output and a growth rate of polynomial-of-output multiplying an unknown constant in the nonlinear terms. By developing a dual-domination approach, an adaptive observer and an output feedback controller are designed to stabilize the nonlinear system by directly utilizing the measured output with uncertainty. Besides, two types of extension are made such that the proposed methods of adaptive output feedback stabilization can be applied for nonlinear systems with a large range of sensor uncertainty. Finally, numerical simulations are provided to illustrate the correctness of the theoretical results.
Cuttings of Populus cathayana Rehd, originating from three triploid and one diploid populations with the same parents but different gamete origins, were used to examine physiological responses to drought stress and rewatering by exposure to three progressive water regimes. Progressive drought stress significantly decreased the leaf relative water content (RWC), photosynthesis, and chlorophyll fluorescence parameters, and increased the relative electrolyte leakage, malondialdehyde (MDA), free proline (Pro), and antioxidant enzymes, such as superoxide dismutase, peroxidase, and catalase, in the four populations evaluated. However, compared to the diploid population, triploid populations showed lower relative electrolyte leakage and MDA, higher RWC and Pro content, and more efficient photosynthesis and antioxidant systems under the same water regime. Our data indicated that triploid populations possessed more efficient protective mechanisms than that of diploid population with gradually increasing drought stress. Moreover, some triploid genotypes were less tolerant to water stress than that of diploids due to large intrapopulation overlap., T. Liao, Y. Wang, C. P. Xu, Y. Li, X. Y. Kang., and Obsahuje bibliografii
In consideration of their origin the adaptive strategies of the evergreen species of the Mediterranean maquis were analysed. Rosmarinus officinalis L., Erica arborea L., and Erica multiflora L. had the lowest net photosynthetic rate (PN) in the favourable period [7.8±0.6 μmol(CO2) m-2s-1, mean value], the highest PN decrease (on an average 86 % of the maximum) but the highest recovery capacity (>70 % of the maximum) at the first rainfall in September. Cistus incanus L. and Arbutus unedo L. had the highest PN during the favourable period [15.5±5.2 μmol(CO2) m-2s-1, mean value], 79 % decrease during drought, and a lower recovery capacity (on an average 54 %). Quercus ilex L., Phillyrea latifolia L., and Pistacia lentiscus L. had an intermediate PN in the favourable period [9.2±1.3 μmol(CO2) m-2s-1, mean value], a lower reduction during drought (on an average 63 %), and a range from 62 % (Q. ilex and P. latifolia) to 39 % (P. lentiscus) of recovery capacity. The Mediterranean species had higher decrease in PN and stomatal conductance during drought and a higher recovery capacity than the pre-Mediterranean species. Among the pre-Mediterranean species, P. latifoliahad the best adaptation to long drought periods also by its higher leaf mass per area (LMA) which lowered leaf temperature thus decreasing transpiration rate during drought. Moreover, its leaf longevity determined a more stable leaf biomass during the year. Among the Mediteranean species, R. officinalis was the best adapted species to short drought periods by its ability to rapidly recover. Nevertheless, R. officinalis had the lowest tolerance to high temperatures by its PN dropping below half its maximum value when leaf temperature was over 33.6°C. R. officinalismay be used as a bioindicator species of global change. and L. Gratani, L. Varone.
We investigate the control of dynamical networks for the case of nodes, that although different, can be make passive by feedback. The so-called V-stability characterization allows for a simple set of stabilization conditions even in the case of nonidentical nodes. This is due to the fact that under V-stability characterization the dynamical difference between node of a network reduces to their different passivity degrees, that is, a measure of the required feedback gain necessary to make the node stable at a desired solution. We propose a pinning control strategy that extends this approach to solve the tracking problem, furthermore using an adaptive controller approach we provide a methodology to impose a common reference trajectory to a network of different nodes by pinning only a few of them to the desired solution. We illustrate our results with numerical simulation of well-known benchmark systems.
A method based on the adaptive-network-based fuzzy inference system (ANFIS) is presented for computing the narrow aperture dimension of the pyramidal horn. Eight optimization algorithms, least-squares, hybrid learning, Nelder-Mead, genetic, differential evolution, particle swarm, simulated annealing, and clonal selection, are used to optimally determine the design parameters of the ANFIS. The narrow aperture dimension computed by using the ANFIS is used in the optimum gain pyramidal horn design. The computed gains of the designed pyramidal horns are in a very good agreement with the desired gains. When the performances of ANFIS models are compared with each other, the best result is obtained from the ANFIS model trained by the least-squares algorithm.
The paper analyses the arguments put forward by Plantinga to justify his refutation of evolutionary reliabilism, i.e. the claim that the probability that the cognitive faculties, developed in the process of unguided evolution, are reliable is low. I argue that all the thought experiments offered by Plantinga to justify this thesis suffer from a common defect – they disregard the condition of evolution or fail to take it into account properly. In addition, I argue that pointing out the difficulties that naturalistic approaches have in explaining mental causation does not lead to Plantinga’s conclusion that in a naturalistic world there would be no mental causation whatsoever.
Adaptivně administrované testy s dichotomně skórovanými položkami jsou již v odborné literatuře poměrně dobře popsány a v praxi jsou stále častěji využívány. Předložená studie popisuje a hlouběji analyzuje možnosti adaptivní administrace testů s polytomními položkami, které jsou nejčastěji využívány v široké oblasti diagnostiky osobnosti. Na základě rozboru adaptivní administrace testu NEO PI-R jsou prozkoumány výhody a nevýhody tohoto přístupu. Adaptivní administrace ve srovnání s plnou délkou testu úspěšně rekonstruuje úroveň všech měřených rysů, a to za použití výrazně nižšího počtu položek. Výrazným problémem je však nadužívání několika málo položek, které jsou charakteristické vysokou mírou rozlišovací účinnosti. Pro studii byl využit reprezentativní soubor osob, který byl sestaven za účelem standardizace dotazníku NEO PI-R v českých podmínkách (N = 2084). and Adaptive administration of NEO PI-R: limits and benefits
Adaptively administered tests with dichotomously scored items are already well described in the relevant literature and used in practice. The presented study analyses the possibilities of adaptive administration of test with polytomous items, which are commonly used in personality testing. Based on analysis of simulated adaptive administration of NEO PI-R, the limits and benefits of this approach are discussed. It was found that adaptive administration successfully and more effectively reconstructs the level of measured traits ADAPTIVNÍ ADMINISTRACE NEO PI-R: VÝHODY A OMEZENÍ1 MARTIN JELÍNEK, PETR KVĚTON, DALIBOR VOBOŘIL Psychologický ústav AV ČR, Brno in comparison with full scale administration. On the other hand, significant problem consists in overexposure of several items with highest item discrimination power. Representative sample built for the purposes of Czech standardization of NEO PI-R was used (N = 2084).
Dlouhou dobu se předpokládalo, že populace obývající určitá území Evropy také tato území na konci doby ledové kolonizovaly jako první. Nové výzkumy však ukázaly, že v některých případech byla první příchozí populace později nahrazena jinou, pocházející z jiného glaciálního refugia. Náš článek ukazuje, že k takovému nahrazení jedné populace druhou došlo při kolonizaci Velké Británie norníkem rudým (Clethrionomys glareolus) a že při tom hrály roli fyziologické adaptace způsobené mutací v hemoglobinu., It has long been assumed that the populations that first colonized particular empty territory after the last ice age have remained there until the present day. However, recent findings in small mammals suggest that replacements involving a population from one glacial refugium at the cost of a population from another refugium may have been a not infrequent event. The article demonstrates that such population replacement took place during post-glacial colonization of Great Britain by the Bank Vole (Clethrionomys glareolus) and that physiological differences conferred by haemoglobin have probably played a role in this process., and Petr Kotlík, Silvia Marková, Karolína Filipi, Michaela Strážnická, Jeremy B. Searle.